Track Calibration Point Pair

First of all: Thanks for this great tracking tool! It's very easy and fast to use.

But I got a problem with tracking the Calibrations Points. So I created the points as the help-pdf says and marked them with the shift-click. Now I want these points to stay at the points of interest although they move in the video. So I thought let these points become trackpoints. But they keep their position and when I open the Track-menu and choose Calibration Point A it says: "Please click the video feature you wish to autotrack. Mouse over the controls above to learn more..."But I already chose the points of interest. So I don't know why the search-button is grayed out.

Hints and help welcome.

Thanks!

Martin

Edit: My aim is a coordinate system which tracks a moving object

And how can I define a second key frame? I want to track two points of a moving object and I am searching for a solution without a second masspoint (because the tracking of 1800 frames takes almost 15 minutes -> this is one single minute of the video I want to analyse)